3-Chloro-2,4-dimethyl-benzenesulfonyl Chloride is an intermediate in the synthesis of 3-Chloro-Vortioxetine (C424140) which is an impurity of Vortioxetine (V766000), a multimodal serotonergic agent. Vortioxetine inhibits 5-HT1A, 5-HT1B, 5-HT3A, 5-HT7 receptor and SERT.